Certain clinical and cardiac necropsy findings are described in 152 patients aged 16 to 78 years (mean 45) with idiopathic dilated cardiomyopathy (IDC): 109 (72%) were males and 43 (28%) were females. Compared to the women, the men had a significantly (p less than .05) shorter mean duration of chronic congestive heart failure (CHF) (43 months - vs - 69 months), a higher percentage of habitual alcoholism (40% - vs - 24%), and a higher mean heart weight (632 g - vs - 551 g). Of the 152 patients, 148 (97%) had clinical evidence of chronic CHF.